The present invention, in some embodiments thereof, relates to wireless communication and, more particularly, but not exclusively, to methods and systems to establish and maintain communication sessions with cellular network subscribers.
As commonly known, there are many mobile or cellular services providers in the world, usually more than one in a single country. These cellular services providers include, but are not limited to, service providers who provide mobility services using global system for mobile communications (GSM), general packet radio service (GPRS), third generation (3G), code division multiple access (CDMA), time division multiple access (TDMA), personal handy phone system (PHS), wideband CDMA (WCDMA), integrated digital enhanced network (IDEN) and wireless local loop (WLL) technologies or their variants. These cellular services providers provide voice, cellular messaging and data services to their own subscribers and to subscribers from other networks.
As commonly known, wireless networks use numeric identifiers to communicate with Mobile Stations (MS) over an air interface. Messages or communications exchanged between the wireless network and MS contain remotely acquired identification data that permits the network to distinguish between different MS while performing operations related to calls and roaming. For example, GSM based wireless networks are specified to support an international mobile station identity (IMSI) as the identifier for MS so that billable services can be provided to international roamers. The IMSI is a unique identifier up to 15 digits in length allocated to each mobile subscriber. The IMSI is a unique identifier is stored, for example, in a subscriber identification module (SIM) card, along with other confidential information known only to the SIM and the cellular services provider to whom the SIM card belongs.
The term “identification data” as defined herein, refers to data that contains information regarding the identity of a mobile device such as a mobile phone, a mobile tablet, smart cameras and a portable computer, wherein the identity information is typically kept on a removable device such as SIM card (the removable device is referred to herein, with no limitations, as a “SIM card”). It should be noted that the mobile device may store identification data on the SIM card. Example SIM cards that are currently in use include SIM cards, USIM cards and UICC cards. They may be marked as such or a combination thereof.
When a mobile device in a GSM network attempts registration to a particular cellular services provider, the most basic mandatory element the mobile device is required to provide is a global unique identity, i.e. the IMSI, so that the cellular services provider may be able to provision billable services for that mobile device. This unique identity is typically stored in a particular SIM card, along with other confidential information known only to that particular SIM and to the cellular services provider that owns that particular SIM.
Upon presentation of the unique identity, and optionally periodically, the cellular services provider attempts to authenticate the received unique identity through procedures described in 3GPP 33.102, which is incorporated herein by reference, by sending an authentication message to the SIM card via the mobile device. Using confidential data known only to the SIM and the cellular services provider, the SIM generates a response message and the mobile device sends that response message to the cellular services provider.
In embodiments where no SIM card is presented and the identity of the mobile device is effectively stored remotely, as described in WO/2012/140654, which is incorporated herein by reference as if fully set forth herein, there may be situations in which time no valid identity can be presented or the previously presented identity cannot complete the initial authentication process or a periodic authentication process. This may be due to the fact that a connection to the remote identity has yet to be established, configuration issues, connectivity issues between the mobile device and the remotely stored identity, or other transient ailments.
Under normal conditions this would typically result in the mobile device prompting the user that no SIM card exists and that he/she must reboot his/her mobile device. The mobile device may also prompt the user with a message to replace the SIM card or remove the SIM card.
There is therefore a need, when the identity of the mobile device is effectively stored remotely, and no valid identity can be presented or be authenticated, to prevent the mobile device from prompting the user with a notification that no SIM card exists and that he/she must reboot his/her mobile device.